Transmission



@et 7, i952 R. J. MELLER @TAL TRANSMISSION 2 SHEETS--SHEET 2 FiledyNov.28, 1947- ATTORNEY Patented er. 7, 19552 rmansivnssmn l Raymond J.Miller, Curt H. Garmager, and Gordon E. Whelpley, Detroit, Mich.,assignors to Bendix Aviation Corporation, Detroit, Mich., corporation ofDelaware Application November 28, 1947, Serial No. 788,388

i 8 Claims. 1

This invention relates to transmissions.-

Broadly thel invention comprehends an innitely variable transmissionincluding a hydrodynamic structure combined with a plurality ofplanetary gear systems.

An object of the invention is to provide an automatically operativetransmission in which the transition from one stage of operation toanother may be effected smoothly so as to avoid shock with the resultantinjurious effectr on the transmission.

Another object of the invention isto combine a hydro-dynamic structurehaving a two-path power iiow with planetary gear systems so as toprovide a transmission that will quickly pick up a load and willautomatically shift to various.

stages of operation as a :result of changes in speed and torque demand.

Another object of the invention is to provid a transmission comprising afluid torque converter combined with planetary gear systems and toeffectively couple the respective elements of the converter to theplanetary gear systems so as to render the transmission fully automaticin its operations.

A further object of the invention is to provide a transmission includinga torque converter and two planetary gear systems arranged coaxiallywith relation to one another,the driving element of the converter beingconnected to the forward planetary gear system, the driven "elenient ofthe converter being connected to both planetary gear systems andthereaction element being detachably connected to the rear ture, a iiuidtorque converter, planetary gearY systems and an output structure soarranged and connected that the reaction element of the converter mayfunction as a brake to retard rotation of the output structure.

' Other objects and advantages of the invention will appear from thefollowing descripticnwhen taken in connection with the drawings forminga part of this specification, and in which:

Fig. 1 is a, longitudinal sectional view of a transmission embodying theinvention, andy Fig. 2 is a diagrammatical illustration of thetransmission. Y

Referring to the drawings for more speciio details of the invention, IIJindicates a bell housing Xedly supported on a plate vl2 adapted-to besecured to` thevblock of aninternal combustion engine having a crankShaft I4 extended verter indicated generally at 2.

torque converter includes a driving element or- -the driving shaft 32.

through the plate I2 into the bell housing i8 in concentric relationthereto, and a iiange I6 on the shaft has secured thereto a hub l,supporting a rotatable housing 2D having a hub 22 oppositely andconcentrically disposed with relation to the hub I8, and a sleeve 2lsplined to the hub 22 has a peripheral flange 26 connected to aplanetary gear system indicated generally at 23.

The hub i3 has therein a bearing 3i) supporting one end of a drivingshaft 32. The shaft extends through the housing 29 and the sleeve 213splined to the hub 22 and has on its other:

end a hub 3eV carrying a flange 36 connected to a, planetary gearingsystem indicated generally at 38, and the hub 34 has thereina bearingsupporting a drivenv shaft 4B alsojournalled in a suitable bearing onthe housing l2).

The housing `.2li encloses av fluid torque con- As shown, the

an impeller Mya driven element preferably a two-stage turbine 46 and areaction member 48 cooperating with one another to provide a toroidaluid circuit. i .f

The impeller 44 includes a shroud 5U bolted or otherwise secured to ahub 52 splined on a v tubular shaft 54' journaled'on suitable bearingsin the 'sleevev 2li, and thek shroud 50 has thereon equi-spaced blades15S-supporting an inner shroud 58.

The turbine 4e includes a hub 60 splined to The hub has a flange 82supporting an outer shroud B4 having thereon equi-spaced vanes 66'supporting an inner shroud'68. This structure constitutes the first'stage of' the turbine and the second stage of the turbine includes anouter shroud 'I0 bolted or otherwise secured to a tubular shaft 'l2extended through the tubular shaft 55 and journaled on suitable bearingstherein, and the shroud l f has arranged thereon equi-spaced vanes 'Msupporting an inner shroud 1t suitably secured to the inner shroud 68 ofthe rst stage of the `8l) extended through the shaft l2 and supported onsuitable bearings therein and in spaced relation to the shaftlZ and thedriving vshaft 32, so as to provide iiuid passages 82 and 84 for the i-circulation of iiuid. The iiange 'i8 supports an outer shroud 85 andequi-spaced vanesI 88, ar-

ranged on the shroud 86 support an inner' shroud 1 90 for cooperationwith the inner shrouds of the impeller and the turbine.

The planetary gear system 28 includes a sun gear 92 splined to anddriven by the shaft 'l2 flxedly connected to the turbine 64. The sungear 92 is in mesh with planet pinions 94 mounted for rotation on asuitable carrier 96 fixedly connected to the hub 22 of the rotatablehousing 29 as by the sleeve 24 and flange 26, and a ring or orbit gear98 in mesh with the planet pinions 94 is carried on a drum |00 fixedlysecured to a flange |02 on the shaft 54 supporting the impeller I4.

The planetary gear system 28 is hydraulically controlled. As shown, aflange |04 splined to the shaft 12 carrying the sun gear 92, supports adrum |06, and a, friction band |08 for cooperation with the drum iscontrolled as by fluid pressure actuated unit |0 connected in the fluidpressure system, supplied as by a pump |||2 driven by the gear ||4 onthe sleeve 24 connected to a prime mover and by a pump ||6 driven by the`gear ||8. on the driven shaft 40. The planetary gear system 28 is alsocontrolled ,as by a clutch having its cooperative elements connected tovthe sun gear 92 and the orbit gear 98 respectively, and a fluid pressureactuated unit |22 connected in the fluid pressuresystem serves tocontrol the clutch.

The planetary gear system 38 includes a drum or housing. |24 supportedfor rotation, on suitable bearings fitted on thedrivenvshaft 40 and theshaft 88 carrying thevreaction member 48, and

. a sun gear |26 carried'by the drum meshes with planet pinionsV |28mounted for rotation on a car-f i rier |30 splined or otherwise securedto the driven shaft 40, and the planetpinions mesh with a ring or orbitgear |32 carried on the flange 36 of `the driving shaft 32.

The planetarygear system 38 is controlled byg a brake operative to holdthe sun gear |26. The brake includes a frictionelement |34 controlled bya fluid actuated unit iI 36 connected in the fluid pressure system.V Theplanetary gear system `38 is also controlled by a clutch |38 operativeto lock theV sun gear |26 to the reaction member 48. The clutch |38includes cooperative elements carried by the shaft 80 lconnected to thereaction member 48 and the drum |24 respectively, and the clutch isunder control of a fluid pressure unit |40 connected in the fluidpressure system'.I

The planetary gear system 38 is further controlled by a clutch |42operative to lock the sun gear |26and the carrier |30 of the planetpinions |32 together, andthe clutch |42 includes cooperative elementscarried-by the drum |24 supporting the sun gear |26 and the carrier |30for the planet pinions.

In the structure hereinabove described in detail,

a fluid torque converter including an impeller:

44, a two-stage turbine 46 and a ,reactionmember 48 has a planetaryVgear system 28 arranged for operation before the converter and aplanetary gear system 38 arranged for operationafter the converter. 4

When in neutral position power from a-prime" mover of the internalcombustion engine is impressed through the rotatable-housing20, thesleeve 24, and the flange 26.0nthe carrier; 96 of the planet pinions.94.. The ypower vtransmitted to the planet pinions issplit sogthatzpartis transmitted to the sun gear. 92andtheremainderto the orbitv gear 98.That portion .of the ipower transmitted to the .suneear 92 flowstherefrom through the shaft '|2- direct to `theturbine46 and thatportion of the power transmitted to the orbit gear 98 flows therefromthrough the drum |00, the flange |02 and the shaft 54 to the impeller 44causing rotation thereof with the resultant energization of fluid in thecircuit and the transmission of power through the medium of the fluid'Ehe reaction member 48 is free to float in the circuit, hence in thisinstance the torque converter 42 functions as a fluid coupling. There isa two-path flow of power from the planetary gear system 28 to theturbine 46 and the power received by the turbine is transmittedtherefrom through the ange 36 on the shaft 32 to the orbit gear |32 ofthe planetary gear system38 which idles during this stage.

When it is desired to move forward, the brake |34 and the clutch |38 areapplied due to increase of pressure on the fluid in the system. This fresults in holding the sun gear |26 and locking the reaction member 48thereto. Under this condition powerimpressed Vby theprime mover on theplanetary` gear systemr28 is split thereby so thatvpart ofthe powerflows direct from thesun gear 92 to the turbinevand .the remainder fromthe orbit gear to the impellerd, from which it is transmitted throughthe medium of the fluid in the circuit tothe turbine-and to Vthereactionmember which, in this instance, is held against movement so thatthetorqueconverter may operate with torque multiplication, andthe powerreceived by the turbine is transmittedtherefrom through the shaft `32 tothe planetary` gear system 38, where ,the torque is again multiplied andtransmitted to Ithe driven shaft.

Upon increase in speed to the extent that thc torque converterno longervmultiplies the torque, the clutch |20 is automatically -applied due toincreased pressure on the fluid in the system to lock the planetary gearsystem,28 for rotation as a single unit connecting theimpellerandturbine directly to the prime mover, andsimultaneously therewith theclutch |38 due to decrease of pressure in the fluid'pressureactuatedunit |40 is automatically released so that the-reaction member may runfree. Under this-y condition, the brake|34 being still applied, thetorqueof the prime mover is transmitted directly through the planetarygearing system 38 withltorque multiplication to the driven-,shaft 40.

Upon further increase ,in` speed to theextent where torque demanddecreases, the-pressure on theffluid inthefluid pressure actuated unit|36 decreases andthebrake |34 `is automatically released. The clutch |42due to increase of Ypressure in the fluid pressureactuated unit |44l issimultaneously-and automaticallyapplied so as to synchronize the prime`mover with the driven shaft 40 and the clutchA |38 lis automaticallyapplied by thefluid actuated unit'|40 so that all of the moving` partsyof lthetransniission may rotate at the same speed soasto reducedrag.

Upon a material decrease in speed; the transmission automaticallyreturnsto the first stage of the forward -drive wherein the; torque converter42 again comesinto operation, except that ther clutch |38 is releasedtothe zend that the reaction member A48, free'wheelsso that the torqueconverter 42-may function -as a fluid-coupling. Under this condition thetorque :output of theturbine unit is reduced to that of the prime moverwhen idling, multiplied only:- by the-planetary gear system. 38 `coupledbetween' the. driving and driven shafts.

.To effect abrakilngl operation, 1the fluid presageicgvei mission to itsAsecond phase of 'forward drive wherein the planetary gear system 28 islocked for rotation as a singleunit and serves to couple theimpellerland thefturbine to the prime mover. While in thisstag'e ofoperation the clutch |38 is applied to hold l the reaction memberagainst movement, andunderthis condition torque, due to forward rotationof the rear wheels, is absorbed by the reaction member 48 resisting'rotation of the impeller and the turbine through the medium of thefluid in the vortexchamberiand bygthe prime mover to effectively resistforward rotation of the lwheels. Y

To effect areverse drive the brake |88 is manually applied so as tohold-the turbine stationary. The clutchV |28, the brake |34 and theclutch |42 are automatically released because of decreased pressure inthe accompanying fluid pressure actuated units |22 and |44 andthe clutch|38 is automatically applied by increased pressure in the fluid pressureactuatedf'unit |40 to lock the reaction member 48 to the sun gear |26 ofthe planetary gear system 38. Under this condition power from the. primemover impressed on ,the planetary gear system 28 flows therefrom to theimpeller d4, causing rotation thereof with vthe resultant energizationof the fluid in vthevortex chamber and the energy of the fluid isreceived by the reaction member causing the member to rotate inthereverse ,direction `and the` power re- D ceived by the reaction memberis transmitted therefrom through the shaft 80, the clutch |38, the drum|24 to the sun gear |26 and through the planet pinions |26 to the drivenshaft l4|), causing the shaft to rotate in the reverse direction. Ininstances where it is desired to start the prime mover as by towing,shift is'made as in the rst stage of 'forward drive. When in thisposition upon rotationA ofthe driven shaft 40, the clutch |28 is applieddue to increased pressure in the iiuid pressure unit |22 to lock theplanetary gear system 28 for rotation as a single unit servingto connectthe impeller and turbine to the prime mover, the clutch |38 due toincreased pressure in the pressure actuated unit |48 is applied soastolock the reaction member 48 to the sun gear |26 of the planetary gearsystem 33 and theclutch |42 dueto increase of pressure in the pressureactuated unit |44 is applied to lock the planet pinions |28 of .theplanetary 'gear system 38. Under this condition power/.flows from thedriven shaft through the planetary gear system 38, thence through thedrive shaft `32 through the turbine and impeller` to the planetary gearsystem 28 and then to the prime mover.

While this invention has been described in connection with certainspecific embodiments, the principle involved is susceptible of numeroustial for y"operation ofthe driving, and driven elements .as a single.unit, abrakef for the power splitting differential :for holding theturbine and utilizing the reaction-element as a driven element foreiecting reverse drive, 'fa driving shaft connected" to .the-drivenelement, a driven shaft, powermultiplying gear `connected between thedriving and driven shafts, means'for connecting the reaction elementtothe Ipower multiplying gear, a. brake for-holding one `element of thepower multiplying gear-to eiect torque multiplication and means forlocking thegpower multiplying gearfor -rotation as a single unit.

1:2...A variable speed transmission comprising a power input shaft, ahousing connectedthereto for rotation therewith, a iiuid ktorqueVconverter including an impeller, a turbine. and a vreaction member inthe housing,l a first -planetary gear systemV including a sun gear,planet pinions and an orbit'geanmeans connecting the planet pinions totheihousing, means connecting the orbit gear. to. the ,impeller,meansconnecting the sun gear to the-turbine, means for locking the `sungear to the orbitgear for rotation as a single unit, a driving shaftconnected to the turbine, an output shaft, a second planetary gearsystem connected between the driving shaft and the output shaft, thesecond planetary gear system including a sun gear, a carrier on theoutput shaft, planet pinions on the carrier and an orbit gear on thedriving shaft, a clutch for connecting the tation therewith, a fluidtorque converter including an impeller, a turbine and a reaction memberarranged for cooperation with one another within thehousing, a planetarygear system including a sun gear, planet pinions and -an orbit gear,means connecting the pinions to the housing,

means connecting the orbit gear to the impeller,

means .connecting the sun gear to the turbine, iiuid pressureactuatedmeans for locking the planetarye` gear system, `a Afluidactuatedbrake for the sun gear, aldriving shaft connected to theturbine, `anoutput shaft, a planetary gear sysother application thatwill readily occur to persons skilled in the art.

Having thus described the various features of the invention, what weclaim as new and desire to secure by Letters Patent is: l

1. A variable speed transmission comprising an input structure, driving,driven and reaction elements cooperating with one another and providinga vortex chamber for the circulation of fluid, a power splittingdifferential connected to the input structuremeans directly connectingthe power splitting diiferential to the driven element, means connectingthe power splitting differential to the driving element for thetransmission of power through the medium of the iiuid in the vortexchamber to the driven element, means for locking the power splittingdifferentem} connect ing,the driving shaft to the output shaft, aiiuidpressure actuated clutchfor connecting the reactionmember to thesun gear of the last mentioned planetary gear system, a brake forholding the sun gear of the last mentioned planetary gear system, and afluid actuated clutch for locking together the sun gear and pinions ofthe last mentioned planetary gear system.

y4. A vvariable speed transmission comprising power input structure,cooperative driving, driven and reaction elements providinginconjunction with one another a chamber for the circulation of fluid, a4power splitting differential connected to the input structure andoperative to transmit part ofthe power directly to the driven elementand the remainder to the driving element for transmission therefromthrough the medium of the fluid to the driven element with torquemultiplication, means for locking the power splitting differential so asto drive the driving and driven elements as a single unit, a drivingshaft connected to the driven element, a driven shaft, torquemultiplying means coupled between the shafts, a clutch 'forconnectingthe reaction element to'thei. torque multiplying means, and means 'forlockingI the torquemultiplying means to effect a direct drive betweenthe shafts.

5. A variable speed transmission comprising a power input structure,cooperative driving, driven and reaction elements providinginconjunction with one anothera vortexchamber for the circulationof fluid,apower' splitting differential connected to the power. input. structureand adapted to transmit part of thepower to the driven element andtheremainder to the driving element forv transmission l through :the mediumof the fluid to the driven element, said power splitting differentialincludingasun gear connected to the driven element, a carrier connectedto the input structure, planet pinions on the carrier and an orbit gear'connected to the driving element, means forlocking together the sungear and the orbit gear of the power splitting differential for rotationas a single unit, a driving shaft connected to the driven element,afdrv'en shaft, torque multiplying means coupled between: the drivingand driven shafts and includinga sun gear, a carrier connected to thedrivenshaft, planet pinions on the carrier and an orbit gear connectedto the driving shaft, fluid-pressure actuated means for connecting thereaction element to the sun gear of the torque multiplying means, andfluid pressure actuated means for locking together the sun gear and thecarrier for the planet pinions of the torque multiplying means.

6. A variable speed-transmission comprising a power input structure,cooperative driving, driven and reaction elements, a power `splittingdifferential including a` sungear connected to the driven element,acarrier connected to the power input structure, planet pinions on thecarrier 'and an orbit gear connected to the driving element, a poweroutput structure, a torque multiplying structure including a sun geaiyfa'carrier connected to the output structure', planet pinions on thecarrier and an orbit gear connected tothe driven element, a fluidpressure actuated unit automatically operative at a predetermined speedof operation of the transmission to lock together the sun gear and theorbit gear of the-power splitting differential, a iluidpressureactuatedunit associated with the torque multiplying structureautomatically operative-to release'thereaction element simultaneouslywith the locking together of the sun and orbit gears of the powersplitting differential, and a fluid pressure actuated unit automaticallyoperative at an increased speed to lock together the sun gear and thecarrier of the lplanet. pinions of the torque multiplying'structure soas to provide for direct drive.

7. A variable speed transmission comprising power input and outputstructures, cooperative driving, driven and 'reaction elements, a powersplitting diiferential connecting the input structure to the driving anddriven elements, a torque multiplyingstructure connecting the drivenelement toftheoutput structure, a fluid pressure actuated unit forcontrol of the power splitting differential operative to lock thedifferenial at a predetermined speed, a fluid pressure actuated unitassociated with the torque multiplying structure for control ofthereaction element operative to lock the reaction element to the torquemultiplying structuresimultaneouslywith the locking of the powersplittingdiflerential, a fluid pressure actuated `brake for the torquemultiplying structure,and auid pressure actuated unit for locking thepower multiplying structure upon attaining a one-to-one ratio drive ofthe input and output structures;

8. 'A variable speed transmission comprising a power input structure, afluid torque converter including cooperative impeller, turbine andreaction elements, Ia. power splitting differential connecting'the powerinput structure to the impeller and the turbine, a fluid pressureactuated unit for locking the power splitting structure, an outputstructure, a torque multiplying structure connecting the turbine to theoutput structure, a fluid pressure actuated unit for locking thereaction element to one element of the torque multiplying unit, and afluid actuated brake for holding the same element.-

RAYMOND J. MILLER. CURT H. GARMAGER. GORDON E. WHELPLEY.

y yR-nFEmaNCEs CITED The following references are of record in the illeof this patent:

2,414,359 f Carnagua Jan, 14, 1947

